This invention relates to a driving connection for use between an internal combustion engine and for instance, a rotating casing of a torque converter and having a resilient intermediate part for transmitting drive.
The main operational requirements for such connections are that they should be capable of accepting a certain degree of misalignment and allow a certain degree of axial movement between the connected parts. At the same time the resilience should be such that the connected parts rotate at speeds below the critical speed the whole time, or in some cases, at speeds between the critical speed ranges.
Many types of resilient driving connections are known and, in some of these, the resilience is varied for the transmission of different torques, allowing a critical speed to be exceeded or permitting operation in the critical speed ranges.
In general, known driving connections are expensive and fulfill the requirements to a greater or lesser extent in one respect or another. Such connections include star plates and different kinds of waved discs permitting very high critical speeds to be achieved. Soft rubber elements with a high damping capacity are also used between driving and driven parts in a drive-line fitted with a hydraulic drive.
In my copending application Ser. No. 504,235, filed Sep. 9, 1974, now U.S. Pat. No. 3,940,947, issued Mar. 2, 1976, which is a continuation-in-part of my application Ser. No. 367,376, filed June 6, 1974, now abandoned, there is disclosed and claimed an improved driving connection for rotatably drivingly connecting driving and driven parts. As disclosed and claimed therein, in an arrangement wherein axially extending abutments on one part engage slots in the other part, a first resilient means is interposed between the facing abutment/slot surfaces which engage in the normal drive direction, this first resilient means being relatively stiff and becoming stiffer as the driving load increases with an increased load to stay above the actual frequency of vibration imparted to the resilient means during normal operation thereof. Between the other side of the abutment and its opposed slot surface is provided a second resilient means having a stiffness less than that of the first resilient means but sufficient so as to resiliently urge the opposed abutment/slot surfaces apart causing the drive side abutment/slot surfaces to engage their respective metallic strip, and concurrently preventing backlash and maintaining contact between the latter abutment/slot surfaces via said second resilient means. Such means makes it possible to satisfy the conditions of force transfer during driving and braking as between the abutment and its slot while concurrently permitting movement of the abutments relative to their slots to adjust for misalignment between the driving and driven parts.
These and other goals were satisfied by the arrangement shown and described in my said previous copending application. However, the specific arrangement shown therein, namely one utilizing a coating or sleeve of rubber or other elastomeric material, while capable of carrying out the intended function, has given rise to certain disadvantages. Firstly, a material such as rubber or the like might be less reliable at extreme conditions. For example, it could possibly harden and/or become brittle at extreme temperature conditions. Also, a rubber sleeve or coating of this type tends to be relatively expensive. Thus, there exists a need for providing an arrangement which will permit achievement of the goals of the invention as set forth in my said previous copending application, without the disadvantages thereof.